Turntable for electric toy and model railroad installations

ABSTRACT

A turntable for electric toy and model railroads having a rotatable bridge body and a supporting body therefor, in which the marginal portion of the bridge body has contact members inserted therein which form counter contacts for spring contacts on said bridge body and are electrically connectable to annular current feeding lines on the supporting body.

United States Patent Ernst [451 Dec. 12, 1972 v [54] TURNTABLE FOR ELECTRIC TOY 468,912 2/1892 Hunter ..191/9 AND MODEL RAILROAD 3,534,688 10/1970 Ernst 104/35 INSTALLATIONS 3,198,136 8/1965 Girz ..191/22 2,727,102 12/1955 Saw er ..191 9 [72] hengmmasse 85 2,820,084 l/l958 Shay: ..191/2 2 Nurnberg,Germany [22] Filed: Oct. 5, 1970 Primary ExaminerGerald M. Forlenza Assistant Examiner-D. W. Keen [2]] Appl 77888 Attorney-Walter Becker [30] Foreign Application Priority Data [57] ABSTRACT Oct. 3, 1969 Germany; ..P 19 49 974.2 A turntable for electric toy and model railroads having a rotatable bridge body and a supporting body [52] US. Cl ..104/35, 46/216 therefor, in which the marginal portion of the bridge [51] lnt.Cl. .Q ..B60s 13/02 body has contact members inserted therein which [58] Field of Search...46/216; 104/35,38, 45; 191/9, form counter contacts for spring contacts on said 191/591, 22 bridge body and are electrically connectable to annular current feeding lines on the supporting body.

[56] References Cited UNITED STATES PATENTS 10 Claims, 11 Drawing Figures 631,491 8/1899 Phillips ..191/9 22 1 r" I I I I 2 I AF; 1 I ,I 25: 7 8 l Il 1 I 1 I 3 I I I I I l l I 5% 6 I z 1 I l I 1 l i I I l I I I l I I l l I I E 1Q ea I l I I I 59 1' l H ---28 es"1 L J PATENTEDHEE 2 I 3. 705. 553

sum 2 or 2 INVEN TOR. //or I? 1/- TURNTABLE FOR ELECTRIC TOY AND MODEL RAILROAD INSTALLATIONS The present invention relates to a turntable for electric'toy and model railroad installations, in which the tracks serve for conveying current to the vehicles and in which the operation of the vehicles is effected with low voltage direct current. a

In applicants US. Pat. No. 3,534,688 of Oct. 20, 1970 there has been described a turntable for toy and model railroad installations in which upon themarginal area of the bearing body which receives the turntable bridge there can selectively be mounted track connecting segments, segments with stop tracks or so-called blind segments whereby, when building up a track system, it is possible to providea more or less great number of track connections at various areas on the marginal portion of the bearing body. The not necessary connecting portions may be provided with a segment with stop tracks if the necessary connecting sections are located opposite a connecting segment, and if con necting sections which are located opposite each other remain completely free, the not necessary connecting portions may be provided with blind segments so that the turntable will always present the appearance of a complete turntable.

In this connection, however, an economic current supply with regard to the tracks of the turntable bridge and also with regard to the track connecting segments on the marginal area of the bearing body has caused some difficulties.

It is, of course, possible to supply current to the two track pieces on the turntable bridge through two collector rings in the bottom of the bearing body and through corresponding resilient sliding contacts provided on the bridge. It is furthermore possible through resilient lamellae on the track pieces and through corresponding fixed contacts on the track connecting segments also to supply current to the track exits selected with the bridge. This, however, is rather awkward when direct current is being used for the driving operation of the vehicle and when the condition has to be met that during the rotation of the bridge by 180 the bridge track has to be changed as to its polarity in order always to obtain the same orientation with regard to the driving voltage onthe feeding tracks which are under voltage.

It is, therefore, an object of the present invention to provide a turntable which will overcome the above mentioned drawbacks.

This object and other objectsand advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIG. 1 illustrates a circuit for the supply of driving currentto a toy turntable according to the invention.

FIG. 2 shows a marginal section of the bearing'body of the turntable of FIG. 1 as seen from the bottom.

FIG. 6 represents a further current bridge for connection to the outer annular line and likewise represents a perspective view.

FIG. 7 illustrates a V-shaped connecting contact for connecting the tracks of the track connectingsegments with the contact of the turntable or with the current bridges according to FIGS. 5 and 6.

FIG. 8 represents a radial cross-section through the marginal portion of the bearing body of the turntable.

FIG. 9 shows a number of blind segments as seen from the bottom, said segments having been extrusion molded together so that they are connected together and serve for covering the non-used connecting areas.

FIG. 10 is a bottom view of one of the two ends of the turntable bridge.

FIG. 11 is a front view of the turntable bridge with the spring contacts provided thereon.

The turntable according to the present invention is characterized primarily in that each connecting area of the marginal portion on the bearing body of the turntable is provided with two passages extending from the inside to the outside while the inside of the cylindrical portion adjacent to the plane marginal portion of the bearing body is provided with recesses forming the continuation of the passages and having outwardly leading depressions. Into these depressions, current bridges are insertable which together with a leg located in a recess and the respective adjacent depression forms stationary counter contacts for spring contacts provided on the turntable and by means of a second leg extending through the passage is adapted to be electrically connected to one of two annular current conducting lines arranged on the outside of the bearing body.

Accordingto an advantageous design of the invention, the current bridges may be formed of at least approximately rectangularly bent resilient metal discs which are adapted with a vertical leg tobe placed into the recess on the inner side of the bearing body while with their lower end they are insertable into the adjacent depression. The horizontal leg of the metal disc which extends outwardly through the passage in the bearing body rests on one of two annular current conductors provided at the bottom side of the marginal portion.

The design according to the present invention for the current connections for tracks of a turntable bridge results in a safe current supply thereof. The current bridges are expediently provided only on one side of the bearing body and, more specifically, only where an entrance to the track system or an exit to a barn or a parking track is to be provided.

The design of the current supply for the turntable according to the present invention makes it possible to provide the tracks of the turntable with current only when the bridge occupies a position in which one or two track connecting segments are provided. This has the advantage that those areas of the turntable which are not provided with track connecting segments, a locomotive on the turntable can at these areas not he accidentally put in motion when switching on the driving voltage. Thus, it is merely necessary with those areas of the turntable which are only on one side provided with a track connecting segment, to provide at the opposite side a segment with stop tracks in order to prevent, with a wrong poling of the driving voltage, a

derailing of the locomotive driving toward the wring side. A further advantage of the invention consists in that with the operation of the turntable, no provisions have to be made to prevent a stoppage at those areas which are not provided with a track connecting segment inasmuch as when stopping the turntable bridge at these areas, due to the lack of current of the tracks of the turntable bridge, the locomotive on the bridge cannot leave the same.

According to a further feature of the invention, additional current bridges may be provided which establish an electric connection either from the already mentioned current bridges or directly from the resilient contacts of the turntable to the tracks of the trackconnecting segments.

Referring now to the drawings in detail, FIG. 1 diagrammatically illustrates by dash lines the marginal portion of the bearing body and the turntable bridge and also a number of track connecting segments. The current feeding lines to the turntable are designated with the reference numerals l and 2. The arrangement shown in the drawing furthermore comprises an inner annular current conductor 3 and an outer current conductor 4 which is coaxial to the conductor 3. Both conductors are preferably formed of a round silver-plated copper wire and are connected from beneath the turntable to the marginal area 15. The two straight lines 5, 6 in FIG. 1 diagrammatically symbolize the rails of the turntable bridge while the spring contacts of the turntable bridge which are in electric connection with the rails 5 and 6 are respectively designated with the reference numerals 7 and 8.

The bearing body of the turntable is dish-shaped and comprises a substantially plane bottom 9, an adjacent cylindrical part l0( FIG. 4) with inner teeth 11 for the bridge drive, an outwardly extending adjacent horizontal part 12 with a circular rail 13 for the outer journalling of the turntable bridge, an adjacent cylindrical part 14 and a plane horizontal part 15 adjacent to the cylindrical part 14. The marginal portions 14, 15 have rectangular passages 16, 17 and in addition thereto have round openings 18(FIG. 3).

The bottom side of the plane marginal portion 15 has small studs or pins 19 which in groups of three are arranged radially one behind the other while their spacing from each other is such that the annularly bent-off wires 3 and 4 can be inserted between each two of these studs or pins. The studs or pins 19 are somewhat longer than the thickness of the wire of the two conductors. By heating and flat ending the protruding ends of the studs or pins 19, both wires are connected to the bottom side of the marginal portion 15. On the inner side of the marginal portion 14 and adjacent to the rectangular passages in the upper marginal portion 14, 15 there are provided recesses 20 which are continued in downward direction by depressions 21 in the marginal part 12, which depressions have a horseshoe-like contour when viewed from above. The recesses 20 and the depressions 21 are so dimensioned that approximately rectangularly bent-off contact discs 22, 23; 24, 25, can with their vertical legs 22, 24 be inserted into these recesses and depressions (FIGS. 5, 6, 8).

FIGS. 5 and 6 show the current bridges or contact lamellae in perspective. Both bridges or lamellae are expediently made of spring bronze and prior to their insertion are bent-off not quite rectangularly. Their horizontal legs 23; 25, 25 are inserted into the corresponding passage 16, 17, and the vertical legs 22, 24 are then pressed into the depressions 21 and have their lower end inserted into the depression 21 after it has been resiliently bent. In this way it will be assured that the horizontal legs 23 or leg ends 25 will with a strong spring thrust engage one of the two annular conductors 3, 4 from below (FIGS. 1 and 2). In view of the cranked end 25' of the contact element according to FIG. 6, a contact with the inner annular conductor 3 will be avoided. The shorter perforations 16 are intended for the contact elements 22, 23 in FIG. 5 and the longer perforations 17 are intended for the contact elements 24, 25, 25' shown in FIG. 6. Both contact elements are in this way connected to the annular conductor without soldering and their position in the recess 20 and depression 21 against accidental detachment is firmly secured.

Since, as illustrated in FIG. 1, each bridge rail 5, 6 has both ends respectively provided with a pair of spring lamellae 7, 8, the arrangement of said pairs of spring lamellae 7, 8 relative to the contact elements 23, 25 is such that only one of said pairs of lamellae 7, 8 can contact the contact elements 23, 25 thereby preventing the feeding lines 1 and 2 from being shortcircuited with each other through the two conductors 5, 7; 6, 8. If desired, the contact elements 23, 25' may be arranged only opposite the marginal sections which are to be provided with a track connecting segment.

In order to be able to supply current also to the rails 26, 27 of the track connecting segments 28 through the intervention of the above mentioned contact lamellae, the following means are provided. The. track connecting segments protrude somewhat inwardly beyond the circumference of the depression 21 or the vertical legs 22, 24 of the contact lamellae 22, 23; 24, 25, 25 and on the inner side of the rails 26, 27 are on the same diameter provided with tangentially arranged slots 29 (FIG. 3). V-shaped contact lamellae (FIG. 7) are adapted to be inserted from above into the slots 29. The lamellae 30 are on the outside near their upper end provided with small notches 31a whereby they are held 7 in position in said segment.

The contact lamellae 30 may individually or also together with the above mentioned contact lamellae be mounted on the connecting area. In this way it will be possible to provide track connecting segments on both connecting areas which are located in pairs opposite to each other, said track connecting segments being connected to the current supply of the turntable.

If is is not desired to provide the oppositely located connecting area with a track connecting segment, a segment with stop track 31 is provided at said area. Such segment in the simplest instance consists of a onepiece injection molded member which is provided with short rail sections 32 likewise consisting of synthetic material. The rail sections 32 are near their outer marginal area equipped with short studs or pins 33. If the driving voltage has accidentally been incorrectly poled, the locomotive moving out toward this side will be stopped by the pins or studs 33 without the danger that the locomotive will derail.

In order to connect the track connecting segments and the segments with stop track on the marginal area of the bearing body, these segments are at their bottom side provided with short studs or pins 35, 36 adapted to be inserted in the bore 18 or the perforations 16, 17 whereby said segments can be detachably connected to the bearing body. Of course, if desired, the segments may also be cemented in their respective position to the bearing body so as to be non-'detachably connected to the bearing body of the turntable. The remaining connecting areas which are not required for a track installation are covered by blind segments which expediently have a plane surface and have their bottom side equipped with the same pins or studs 35, 36 as they are required on the other segments.

FIG. 9 illustrates a number of blind segments 34 as seen from the bottom. These blind segments have the bottom side provided with pins 36 or the like to be inserted or pressed into the perforations 16, 17 and also have their bottom side provided with slightly conical pins 35 to be pressed into the bores 18. The outer marginal area is equipped with bead-shaped extensions 37 for purposes of stiffening the outer marginal area. The track connecting segments and the segments with stop tracks have their bottom side designed precisely in the manner of said blind segments.

FIGS. and 11 illustrate one of the two ends of the turntable bridge and, more specifically, FIG. 10 shows the same as seen from the bottom,and FIG. 11 shows the same as seen from an end face. Both ends of the bottom side of the turntable bridge 38 have by means of screws 40 connected thereto an insulating member 39 to which by means of the same screws 40 also two contact bridges '41 are connected. The contact bridges 41 are by means of fitting pins 42 secured in their position with regard to the insulating member 39. The contact bridges 41 expediently are made of spring bronze and are provided with resilient arms 43 each of which rests on a contact pin 44 which is inserted in the bores provided in the insulating member 39. These contact pins 44 are in this way at their upper end under spring pressure held against the bottom side of the rails 5, 6 on the turntable bridge. If desired, instead of this contact connection, also any other suitable connection, for instance, a soldering connection may be provided.

The two contact bridges 41 are equipped with spring arms 45 angled off by 90. These arms 45 have ballshaped ends 46 which protrude somewhat toward the outside beyondthe insulating member 39 so. that the latter when the turntable bridge is inserted into the bearing body, will from the inside under spring pressure engage the marginal portion 14 of the bearing body. The spacing between the two heads 46 is so selected that in an arresting position of the turntable bridge, one of these heads 46 engages the lamellae portions 22, 44 or 30 thereby establishing a safe electrical connection with the current supply. When inserting the contact It is, of course, to be understood that the present invention is, by no means, limited to the particular showing in the drawings but also comprises any modifications within the scope of the appended claims.

What I claim is:

1. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said I supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or .with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical conducting engagement with one of said pairs of spring contacts, each of said pairs of contact members comprising a first and a second contact member having a polarity at one of opposite positions, each contact member being embodied with two legs of which one leg is respectively electrically connected to one of said first and second annular conductors and the other leg being for electrical conducting connection with track segments through one contact of either of said spring contact pairs of said bridge body, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable by one of saidpairs of spring contacts and electrically conductively connectable to the rails of a track segment to be mounted on one of said marginal sections.

2. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical engagement with one of said pairs of spring contacts, each of said pairs of contact membersc omprisi ng a first and a second contact member respectively electrically connected to said first and second annular conductor, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable by one of said pairs of spring contacts and electrically conductively connectable to the rails of a track segment to be mounted on one of said marginal sections, each of said first and second contact members being formed by a resilient metal strip having two legs defining with each other an angle of nearly 90, one of said legs engaging one of said annular conductors and the other one of said legs being engageable by one of said pairs of spring contacts, or by, respectively, the said third and fourth contact members.

3. A turntable according to claim 2, in which each of said marginal sections has first and second passage means including recesses in alignment therewith for detachably receiving said first and second contact members accordingly installed in recesses and also has third and fourth passage means for detachably receiving said third and fourth contact members accordingly installed in recesses.

4. A turntable according to claim 2, in which said first and second annular conductors are formed by round blank co-axially arranged wires connected to the bottom side of side marginal portions.

5. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical engagement with one of said pairs, of spring contacts, each of said pairs of contact members comprising a first and a seems con tact member respectively electrically connected to said first and second annular conductor, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable byone of said pairs of spring contacts and electrically conductively connectable to the rails of a track segment to be mounted on one of said marginal sections, each of said third and fourth contact members being formed by a V- shaped resilient metallic member with each arm of said V-shaped portion provided with a notch at its outer upper edge portion for receiving a portion of a track segment to be connected to the turntable.

6. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for electrical engagement with one of said pairs-of spring contacts, each of said pairs of onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical engagement with one of said pairs of spring contacts, each of said pairs of contact members comprising a first and a second contact member respectively electrically connected to said first and second annular conductor, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable by one of said pairs of spring contacts and electrically conductively connectable to the rails of a track segment to be mounted on one of said marginal sections, the bottom side of said marginal portion being provided with a plurality of groups of three radially aligned pin means, each two adjacent pin means of each group holding a portion of one of said annular conductors clamped therebetween.

7. A turntable according to claim 6, in which each of said annular conductors consists of silver-plated copper wire and each of said first and second contact members is made of spring hard bronze.

9. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical engagement with one of said pairs of spring contacts, each of said pairs of contact members comprising a first and a second contact member respectively electrically connected to said first and second annular conductor, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable by one of said pairs of spring contacts and electrically conductively corinct'able to the rails of a track segment to be mounted on one of said marginal sections, each of said marginal sections having first and second passage means for detachably receiving said first and second contact members and also having third and fourth passage means for detachably receiving said third and fourth contact members, said marginal sections in addition to said passage means being provided with, bores, said passage means and said bores being adapted to receive protrusions on segments to be mounted on said marginal sections.

10. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported bysaid supporting body while being connectab le to a source of electric current, said supporting body including an annular marginal portion'mnfsaid 'aaiTafionaafis mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical engagement with one of said pairs of spring contacts, each of said pairs of contact members comprising a first and a second contact member respectively electrically connected to said first and second annular conductor, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable with one of said pairs of spring contacts, respectively one of said first and second contact members connectable to the rails of a track segment to be mounted on one of said marginal sections, insulating members respectively provided at both end portions of said bridge body, contact bridges connected to the bottom side of said insulating members and provided with arms resilient in vertical direction, electrically conductive pin means inserted in said insulating member and electrically connected to the rails of said bridge body, said contact bridges being provided withresilient spring arms, said contact bridges forming said first and second pair of spring contacts. 

1. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on each side of said bridge body with at least some of said marginal sections for electrical conducting engagement with said first pair of spring contacts only both oppositely located thereon being connected in electrical conducting relationship with track segments of said bridge body, each of said pairs of contact members comprising a first and a second contact member having a polarity at one of opposite positions, each contact member being embodied with two legs of which one leg is respectively electricallY connected to one of said first and second annular conductors and the other leg being for electrical conducting connection with track segments respectively one contact of both said spring contact pairs of said bridge body, and a plurality of pairs of third and fourth contact members having a polarity thereof arranged on said supporting body and engageable by said second pair of spring contacts and electrically conductively connectable to the rails of a track segment to be mounted on one of said marginal sections.
 2. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical engagement with said first pair of spring contacts only, each of said pairs of contact members comprising a first and a second contact member respectively electrically connected to said first and second annular conductor, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable by said second pair of spring contacts and electrically conductively connectable to the rails of a track segment to be mounted on one of said marginal sections, each of said first and second contact members being formed by a resilient metal strip having two legs defining with each other an angle of nearly 90*, one of said legs engaging one of said annular conductors and the other one of said legs being engageable by said first pair of spring contacts.
 3. A turntable according to claim 2, in which each of said marginal sections has first and second passage means including recesses in alignment therewith for detachably receiving said first and second contact members accordingly installed in recesses and also has third and fourth passage means for detachably receiving said third and fourth contact members accordingly installed in recesses.
 4. A turntable according to claim 2, in which said first and second annular conductors are formed by round blank co-axially arranged wires connected to the bottom side of side marginal portions.
 5. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical engagement with saiD first pair of spring contacts only, each of said pairs of contact members comprising a first and a second contact member respectively electrically connected to said first and second annular conductor, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable by said second pair of spring contacts and electrically conductively connectable to the rails of a track segment to be mounted on one of said marginal sections, each of said third and fourth contact members being formed by a V-shaped resilient metallic member with each arm of said V-shaped portion provided with a notch at its outer upper edge portion for receiving a portion of a track segment to be connected to the turntable.
 6. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical engagement with said first pair of spring contacts only, each of said pairs of contact members comprising a first and a second contact member respectively electrically connected to said first and second annular conductor, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable by said second pair of spring contacts and electrically conductively connectable to the rails of a track segment to be mounted on one of said marginal sections, the bottom side of said marginal portion being provided with a plurality of groups of three radially aligned pin means, each two adjacent pin means of each group holding a portion of one of said annular conductors clamped therebetween.
 7. A turntable according to claim 6, in which each of said annular conductors consists of silver-plated copper wire and each of said first and second contact members is made of spring hard bronze.
 8. A turntable according to claim 6, in which each of said pin means has a length exceeding the diameter of said annular conductors and has its free end formed by an enlarged head.
 9. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical engagement with said first pair of spring contacts only, each of said pAirs of contact members comprising a first and a second contact member respectively electrically connected to said first and second annular conductor, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable by said second pair of spring contacts and electrically conductively connectable to the rails of a track segment to be mounted on one of said marginal sections, each of said marginal sections having first and second passage means for detachably receiving said first and second contact members and also having third and fourth passage means for detachably receiving said third and fourth contact members, said marginal sections in addition to said passage means being provided with bores, said passage means and said bores being adapted to receive protrusions on segments to be mounted on said marginal sections.
 10. A turntable for electric toy and model railroad installations comprising a rotatable bridge body with electrically conductive rails forming a railroad track and with a first pair and a second pair of spring contacts, said pairs being respectively arranged at oppositely located end portions of said bridge body and being electrically connected to said rails, said turntable also comprising a supporting body for said bridge body and a first and a second annular electric current conductor insulated from each other and supported by said supporting body while being connectable to a source of electric current, said supporting body including an annular marginal portion having said annular conductors mounted thereon and being provided with a number of marginal sections for selective connection with track segments to be driven over by a rail vehicle from and onto said bridge body or with stop track segments or with blind segments, a plurality of pairs of contact members respectively arranged on at least some of said marginal sections for electrical engagement with said first pair of spring contacts only, each of said pairs of contact members comprising a first and a second contact member respectively electrically connected to said first and second annular conductor, and a plurality of pairs of third and fourth contact members arranged on said supporting body and engageable by said second pair of spring contacts and electrically conductively connectable to the rails of a track segment to be mounted on one of said marginal sections, insulating members respectively provided at both end portions of said bridge body, contact bridges connected to the bottom side of said insulating members and provided with arms resilient in vertical direction, electrically conductive pin means inserted in said insulating member and electrically connected to the rails of said bridge body, said contact bridges being provided with resilient spring arms forming said first pair of spring contacts. 